peugeot 306 Hdi water preheater how effective is it please?

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Jan 2010, 20:31

Hi, I usually frequent the citroen side of the forum but I was wondering
if anyone here knows how efficent the 306 HDi water preheater my be with regard to heating the water up quickly i.e how long is it before the heater puts out warm air in the winter?

I have been thinking about using one of these glow plug water heaters to
heat the water in a Xantia which would in turn heat the fuel filter and the interior but mainly for running on veg oil.

any advice would be appreciated

regards Nigel.

wheeler · Post by **wheeler** » 31 Jan 2010, 21:57

I doubt if anyone would know if any of the glow plugs in it were not working. Waste of metal.

falling-out-with-my-car · Post by **falling-out-with-my-car** » 31 Jan 2010, 23:31

there must be warning lights on the dashboard for this system esspecially as it is run by the ecu. it may be a waste of metal to you but it does have practical uses elsewhere.

spider · Post by **spider** » 01 Feb 2010, 10:43

I think they are mainly intended (or were?) for really cold climates, so you would actually get a bit of heat out of the heater without such a long wait...

Xaccers · Post by **Xaccers** » 01 Feb 2010, 10:49

You'd do better with an inline fuel heater rather than spend time heating the coolant to then heat the fuel.
You could go for a multipoint one, heating before the filter and then between the filter and pump (indirect for that one).

spider · Post by **spider** » 01 Feb 2010, 10:53

I made one for my 205

as the "back of the block" heater was more interested in taking air in.

Pics later today on the appropriate thread.

wheeler · Post by **wheeler** » 01 Feb 2010, 14:50

falling-out-with-my-car wrote:there must be warning lights on the dashboard for this system esspecially as it is run by the ecu. it may be a waste of metal to you but it does have practical uses elsewhere.

There are no warning lights for it. It is ECU controlled but all the ECU does is earth a relay coil to enrgise the glowplugs so there is no fault detection available if the plugs fail. Glow plugs dont have a very long life span & i bet if you took 100 old 2.0 HDi engines & checked the glow plugs in the water heaters Half of them would not be working & the users would not have even noticed. You were asking how efficient they are & the answer is not very.
I believe they are no longer used on newer HDi's.

falling-out-with-my-car · Post by **falling-out-with-my-car** » 02 Feb 2010, 01:07

xac,

I already have an inline fuel heater but the engine is still hunting on cold veg, I though heating the block by heating the water might get the engine up to temperature quicker thus improving running and reducing hunting.
it would increase fuel economny to.

Xaccers · Post by **Xaccers** » 04 Feb 2010, 09:32

Well, the main thing is the heat of the fuel, the heat of the block will just affect the dissipation of that heat.
As you'll know, you just need to heat the WVO enough so that it's still hot enough by the time it reaches the pump to stop it struggling.
Easiest way to do that would be heat the fuel system (a small volume to heat) rather than the coolant system and engine itself, and the easiest way to do that is using fuel line glow plug heaters which heat up a lot quicker than the cooling system does.
So it might be worth having an indirect heater in the fuel line between the filter and pump as well, or upgrade your current heater to one with more glow plugs.

falling-out-with-my-car · Post by **falling-out-with-my-car** » 04 Feb 2010, 09:53

xac, funny youn should mention that, I have been eyeing the fleabay glow plug heater blocks, there is a single glow plug heater as part of the kit that is thermostatic and is designed to sit between the filter housing and the pump.

I shall probably have a go at that, I am wondering if I could find some glow plugs that heat for longer & hotter than my current standard xantia plugs because if I heat them twice starting in cold weather doesnt pose a problem.

cheers Nigel.

Xaccers · Post by **Xaccers** » 05 Feb 2010, 18:48

I'd look into seeing if you could just extend the time the heat for if the filter->pump heater doesn't do the trick.

What plugs and how many do you have in your current inline heater?
Is it direct or indirect?

When I eventually get round to changing Cassy's I may use one of her old ones as a test in some veg to see if it carbonises at all.
Something tells me it won't as there will be very little oxygen in the oil, in which case an inline direct heater could be used between filter and pump.
Or fit a second inline filter after it.
Not being attached to the block, the filter won't zap heat from the fuel

spider · Post by **spider** » 05 Feb 2010, 18:51

I asked the seller a question about one of those (the single plug heater) to see how much power it consumed, I no longer have the mail but I'm sure they said 170W which is about 14A...

falling-out-with-my-car · Post by **falling-out-with-my-car** » 06 Feb 2010, 03:03

Xac
my stanadyne inline heater is direct it doesnt have glow plugs its made of a steel fuel tube covered in a coil along its length and that is covered in an outer sleeve to protect the coil and thermostat.

I have a spare I might install that between the filter and the pump and give it a go, I am still looking at heating the water and in another thread I have found a company in the US called autoparts2020 who sell an inline bottom hose heater they are 650 watt and 120 volts I am trying to get hold of two for my car and wire them in series.

they also do a nice range of cheap heater pumps which pump the coolant around the vechicle. this might heat an xantia fuel filter housing nicely.